[Editor’ Note: Guest writer Nick Coury is the Chief Technology Officer for Aravaipa Running, a race-management company based in Arizona. In this article, Nick discusses the current revival of American ultramarathon performances on the road and track. He also previews the upcoming Desert Solstice Invitational, a 24-hour and 100-mile track race that he directs and that will be held on December 14 and 15, where some more high-level American track performances could occur.]

American ultrarunning is on the eve of a revolution, though it is happening with little fanfare. While ultra-distance events on trails are becoming more ubiquitous, a small group of ultrarunners are rewriting the record books far away from the dirt.

For the past few decades, fast road and track ultras have been the territory of foreigners. World-class 100k and 24-hour runners came from Japan, Britain, Russia, and Greece, among others. As the IAU developed the 100k and later the 24-Hour World Championships, the U.S. made token appearances but was rarely a legitimate contender. Two individual golds by Ann Trason are almost lost among the consistently high performances of overseas competitors.

No longer. Scott Jurek’s transition from trails to road in order to set the 24-hour American record in 2010 foreshadowed what was to come. In the past two years, Americans have dominated the long-distance running scene in extraordinary form. At the 2012 IAU World 100k, the women scored three in the top five for the overall win, led by Amy Sproston’sindividual title. The men placed four in the top 10 for a second-place team finish. That fall, at the 2012 World 24-Hour, Mike Morton won the race, set an American record, and became the third best one-day runner in history. Connie Gardneralso set an American record, leading the women to a team gold. This spring’s World 24-Hour saw yet higher results. Jon Olsen led the men to victory with an individual gold and teammates scoring second and 10th. Sabrina Littlereclaimed the American record from Connie, with the second, third, and fourth-place scores allowing both U.S. teams the win.

The 2013 US 24-Hour Team. Photos courtesy of Nick Coury

The world championships are far from the whole story. The revival of the American ultra-distance track race is just beginning. At the 2012 Desert Solstice, Jon Olsen and Mike Arnstein both broke 13 hours for 100 miles, the first time any American has done so since 1989. Pam Smith was within minutes of breaking 15 hours. In September, Jon Olsen became the first North American to ever break 12 hours (7:12 minutes per mile), becoming the eighth best 100 miler in history and bettering his own PR by 30 minutes. Going longer, we find Joe Fejes putting in a 156-mile one day as a warm up two weeks before his staggering 329-mile, 72-hour performance on the road. This itself is only prep for his comingattempts at breaking the six-day American record. On the flip side, Zach Bitter quietly ran a 5:12:36 at the Chicago Lakefront 50 Mile. The last time someone ran that fast was in 1981, five years before he was born.

All of this naturally draws the question, where are we going? Can Americans approach and surpass the standing world records? Who will be the ones to do it, and what conditions will it take?

Jon Olsen reflects on the prospects of future 100-mile performances, including the world record of 11:28:03 (6:52 minutes per mile) in an interview for this article,

“There are many runners out there capable of running a sub-12-hour 100 mile. It takes a 7:12 average per mile. But for those runners that run a 2:30 marathon or faster… they could down shift by a minute and 20 seconds and do it. However, this kind of race is more mental, than physical… There really is no rest. Unlike a typical trail 100 mile where you have downhill sections to rest, you have to hold your pace and effort every step… I don’t know if I really think I have a chance at breaking the 100-mile or 24-hour [world] records… but I think guys like Sage Canaday, maybe Michael Wardian, could come close because they have faster leg speed. But I think it would also involve a complete training focus to do it. 11:30 is flying!”

For this article, Mike Morton shared his take on Yiannis Kouros’s 24-hour world record of 188.59 miles (7:38 minutes per mile):

“I think we will see the records pushed over time… I think the record Mr. Kouros has established will take a while to achieve. 188 miles is 16 miles more than what I have done, I think 180 will be hit by someone. I think Jon Olson is the guy to do it right now along with a couple guys from Europe… I think if a 24 hour takes place and you have a group of guys or gals all pushing the record pace you will see an off-the-chart new record. 172 is soft and soon I will not be the American record holder. I think Joe Fejes is raising awareness of the multi-day events again as well. I think we might see interest in those events like there was in the ’80s and ’90s.”

Pam Smith also weighs in on the women’s 100-mile track and road world records in an email exchange for this article,

“I think there are several women in the U.S. right now who would have a good shot at running under 14:25 for 100 miles. I think the biggest barrier is just the number of women who have the desire to run 100 miles on the track. The world road record [13:47] was set by Ann Trason and I think that is a really stout time. And there just aren’t that many 100-mile courses with ideal conditions for running as fast as possible. That record could be around for a lot longer.”

A valuable perspective on the subject comes from British ultra-historian Andy Milroy. With decades of firsthand experience, insight, and most importantly, mountains of statistics, Andy knows exactly what kind of runner is needed for a world record. For this article, I asked him his thoughts. First he addresses past and current holders of the men’s record, “The 100 mile as Oleg Kharitonov and Denis Zhalybin showed, and Cavin Woodward and Don Ritchie before them, is really the preserve of the 100k runners. Jon Olsen did well but moving down to sub-11:30 is a different ball game.” After analyzing his list of top 100-mile performances, he makes an interesting observation. “Basically the men’s list for track is dominated by straight 100-mile races, the women’s by 24-hour splits… This indicates that a woman with good 100k credentials could go under 13 hours for 100 miles in a straight race.” And as for the 24-hour world record, well… “No one is going to touch Kouros’s 303k anytime soon!”

The world records won’t be easy, but they certainly aren’t impossible.

There is a lot of momentum building for fast ultras. The draw of the world championships pulls talent from the trail and shorter road events alike. Morton says,

“I think folks hear the stories from the team members and realize it is pretty cool to don that USA jersey and throw down in a world competition… It was a huge motivation for me to run with the potential to be a ‘world champion’ and recognize my country. I think more runners will see that it is a rare opportunity and taking part can be accomplished parallel to running trails.”

A fast ultra can even play a big role in training for trail races, says Smith, “Having a great race at Desert Solstice last year gave me a lot of confidence in my ability to run 100 miles well [at Western States].”

What do we have to look forward to? Lots. The 2014 national teams are shaping up to be the strongest yet. The Desert Solstice Invitational is this weekend with an ever-increasing field and increased prize money for top performances ($250 up to $5,000). The race is organized to provide ideal conditions for runners to set national and world records, qualify for national teams, and achieve significant personal records.

What does this mean in terms of race logistics? First of all, the all-weather track surface is ideal for top performances given its absolute flatness, traction in any weather, and consistently forgiving cushion. Stadium lighting at night prevents midnight fatigue and gives runners a mental boost. The aid station and crew tents are at the outer edge of lane two, keeping aid only a step away without blocking the inner lane. Large displays at the start line provide instant feedback on a runner’s distance, place, and lap times. The timing team keeps a close eye on runner performances, providing runners with the lap splits needed to hit their goals on-demand. This proved crucial for Jay Aldous when he set a world age-group record at 100 miles, as his trance-like focus the last 40 miles was on hitting the required pace one lap at a time.

What does this translate into for runners? Aldous’s time was a 76-minute improvement over his previous best. Or, take Michael Arnstein, coming to the 2011 race with a national-class 15:26:21 100-mile PR. With the advantages of the track, he improved by 100 minutes to clock a 13:46:18. If this wasn’t enough, he returned in 2012 to shave another 49 minutes and clock a 12:57:45. Joe Fejes pushed for a big PR at the 2012 World 24 Hour of 147.48 miles in order to score for the team. Yet, with the improved conditions of the track, Joe ran 156.626 miles three months later at last year’s race.

Jon Olsen and Mike Arnstein racing the 2012 Desert Solstice.

What will this year’s race see? Zach Bitter will be attempting a fast 100 mile, and could threaten Jon Olsen’s recent record. Pam Smith is gunning for the 200k American record, and then planning to push on for a spot on the US 24-hour team. Connie Gardner is a recent entrant, a former American Record holder who is still looking to break 150 in 24 hours. Other runners to watch are Jay Smithbergerwho ran 13:49:13 at Desert Solstice last year and will be gunning for running all 24 hours this year and Olivier Leblondwith a 14:33:25 best at 100 miles; Anthony Culpepper, Anthony Forsyth, and John Maas are all shooting for over 150 miles; Eric Clifton with countless performances; and John Ticerand Roy Pirrung with their strong age-group performances. Spots are still available, and interested runners can inquire to nick@aravaiparunning.com.

Which runners not mentioned in this article do you think could make a dent on some of the American (or world) records discussed here? In vetting for a particular person, please share the racing credentials you think make them a possibility.

Some runners show their ability to perform well on all surfaces, road, track, and trail, while some runners seem to specialize at certain race substrates. Do you think the ability or inability to cross over is a matter of genetics, training, or perhaps a little of both?

At the upcoming road and track events, who among the above-listed contenders has the best shot at reaching their goals? Why do you think this?

I've always been interested by the fact that on the women's side, many of the top runners seem to cross over and excel at both (Ann Trason, Kami Semick, Megan Arbogast, Pam Smith). And I know in talking with some of the other women, when it comes to choosing races, even if there are other races we'd like to do (UTMB and World 100K are the same day in 2014), we would choose to run at an IAU World Championship event, rather than choosing a conflicting trail event, in large part because representing the USA is such an amazing experience and one we're not willing to pass up if given the opportunity. On the guy's side, there doesn't seem to be much crossover, or at least, it's not the top trail runners crossing over to qualify for and run the World Championship events. I'm guessing it has something to do with the pool of talent at the top for men and women–it's just deeper for men, and thus, they have to choose to specialize. Or maybe there are more purists among the top trail guys who don't ever want to run on the road. I'd have to think that Rob Krar could have a phenomenal road 100K and make it to the podium at Worlds. Personally, I like both trail and road, so don't have an issue crossing over because of terrain. I would almost always rather race on trails than roads, but given the opportunity to run for the US team, would choose that.

I've got some really fond memories from races I've completed over the years, but there's nothing quite like standing on the team podium wearing the USA uniform and singing the national anthem.

Wardian was a good name for Nick to mention. Aside from his leg speed, he likes to run a wide gamut of races on a variety of terrain. I would expect him to attempt a 24 hr or fast 100mi some time in the coming years. If he does aim for 24 hours, that will be a long race even for Iron Mike as I believe his longest race to date is 135mi at Badwater.

Another runner who I think is similar to Mike in that respect is Ian Sharman. After his 'slow' summer of 100s, I know he he is running Comrades in June '14. We know he has fast legs for a trail 100 (see RR from a few yrs ago). We shall see if he maintains his fast training past Comrades for a fast 100 (though I don't expect him to aim for a 24hr race).

Yet another distance runner with Fruitarian Arnstein's ability is Oz Perlman. The two of them trained for years together and have been neck and neck with each others' marathon PR time. I believe Oz has the faster PR at the moment with 2:25 in this year's Hartford marathon. I believe his 50mi PR is 5:25 at Lakefront in Chicago (the course record that Zach Bitter broke). He is a thorough-bred roadie used to long road miles (has one DNF and one successful run at Spartathlon), and is young enough to make a lot of waves in the coming years. Time will tell when he'll test out the track. He is competitive enough with Arnstein that I hope Arnstein's time is a carrot dangling in Perlman's face.

Nick Coury, author of the article, who I believe is running Hardrock again, is not one to be ignored. He respects the history and personality of ultra running on trail, roads, and track and has some leg speed to boot. He was humble not to mention himself, but keep an eye out for him.

Mr Coury was smart to mention Sage. Sage still likes roads and he's committed to run the Olympic Trials again. Right now his marathon PR is roughly equal to Barney Klecker's (current owner of the US 50mile with a phenomenal 4:51). Sage likes mountains and trails, but until he stops talking about the Olympic Trials Marathon, he'll never be too far from a road. I don't see him aiming for 24 hours – perhaps ever.

It occurred to me that the previously unknown Zach Miller could be lured to one of these races. He likes trails, but let us not forget he logs lots of treadmill miles. Who knew a track could be so social and exciting. Let's hope he gives in a crack in the future.

The pool of potential runners is large right now, which is one of the most exciting aspects of it all. It reminds me of the early 80s when most of the fast US 50 mile times were run (http://www.lehigh.edu/~dmd1/50miUSA) Basically there was a huge group of road marathoners, all in the 2:20 or below range. Some of them gave their shot at 50 miles and longer, and quite a few that were endurance-geared found success.

I had a discussion with Ian Sharman earlier this year about what kind of runners it will take to run a fast 100 or 24 hour. He's one of the most astute thinkers I've found when it comes to this, including his own potential. It's easy (but misguided) to take a fast marathoner and say they would be great if they stepped up to 100 miles or 24 hours. The argument goes that since they have so much leg speed, they could hold a "casual" pace for much longer. Ian's observation that struck me was that leg speed may be an indicator they will do POORLY at a fast, long ultra.

If you look at Ian, he's got a marathon PR of 2:32, but his half marathon PR is only 1:15. He gets worse (relatively) as the distance gets shorter, and better as it gets longer. That indicates his "peak" distance may be somewhere around 100 miles or 24 hours. Now, take a fast marathoner in the 2:15-2:20 range, that also excels at 5ks, 10ks, half marathons, etc. This runner may be peaking at the marathon and can hold on for a fast 50 mile, but is struggling to do so and is getting relatively worse as the distance progresses. That's why Jon Olsen can only run a 2:27 marathon. If he ran a 2:15 marathon, it would likely indicate his peak is at a shorter distance than 100 miles.

Not to say there aren't exceptions to this, but looking at how a runner scales to each distance is a better sign than their PR at their optimal distance. Just like a world class 800 meter runner can't run at that level for a 10k, a world class marathoner is unlikely to excel at 100 miles and beyond.

Ian ran Desert Solstice last year and had to stop at 70 miles, but when he nails 24 hours I think we'll be impressed with what he can do.

That's an interesting point, and something I've noticed too. I think the fact that the top women have so many diverse racing options also limits where the womens' records get challenged. Right now you and a few other women are pushing the 100k, and a few others (Sabrina Little, Connie Gardner, Suzanna Bon, etc) are pushing the 24 hour. Many consider Ann Trason's 13:47 out of reach because no one else has run close to that. On the other hand, there hasn't been any focus on a fast 100 mile from US women as long as I've been around. When top womens' times on the trail are generally within 2 hours of the top mens' times, I think Andy Milroy's estimate of under 13 hours is spot on.

I'd love to see an attempt at the 100 mile record at Solstice (or elsewhere). The hardest part seems to be fitting it with everyone's busy racing schedules. Hope to see it one year!

I agree with hthe3rd, if Zach Bitter nails it at Desert Solstice this weekend, he can definitely go under Olson's new record. 5:12 at Chicago is blazing fast, and he's not a 100 mile debutante. He's already got last year's WS100 and a 90+ mile effort at Burning River under his belt (DQ'ed at the latter for missing an aid station checkin, I believe). He runs high mileage and should be ready to challenge the record for sure.

The women have done a good job in recent years of cracking into the All-Time Top 10 Lists for 50 mile to 24 hour distances. The men not quite as much, though a few guys have (especially at 24 hours, with new ARs for both men and women). But I think this article properly identifies that we're "on the eve of a revolution". I think you'll see these Top 10 Lists being virtually rewritten in the next five years.

Of particular interest to me, I think both the men and women have the potential to win team gold at the World Champs 100km next year (in Latvia in August) if the top qualifiers participate. This year presents an unprecedented opportunity for folks looking to get on the team as well. With no 2013 Worlds due to cancellation, there are no people autoselected from the previous WC.

The current Standards for Consideration can be found here: http://www.usatf.org/Events—Calendar/2014/IAU-1… Interestingly, the currently posted Standards combine 100km and 50 mile road distances (sub-7:20/8:40 and sub-5:40/6:40, for men and women respectively) with American River, Ice Age, and JFK, all under Criterion 4. Until last year, any road performance that hit the qualifying time automatically had priority over a trail time, no matter how fast, as they were separate criterion—formerly Criterion 4 (road 100km/50 mile) and Criterion 5 (AR, IAT, JFK). Thus, a sub-7:20 100km would be selected before a 5:34 JFK (Max last year), even if 5:34 was quite clearly a superior performance. I think the combining of these two criteria is probably a positive change, assuming I'm interpreting it correctly. Confusing the matter slightly is the currently qualified athletes pool listed at the bottom of the page as Current Qualifiers. This list separates road and trail times, like under the old system. I'm going to email Howard Nippert for clarification. In any event, the point remains: it's easier to get on the team this year than probably any other recent year, since more spots are open.

As I believe Scott Jurek was quoted in an article recently the 24 hour race is the Pinnacle of Ultrarunning. I concur wholeheartedly and also believe the short loop event along with multiday running represents ultrarunning's greatest appeal to mainstream spectators. Runners and non runners can easily relate to a 24 hour period. Will Madison Square Garden be sold out again to witness the 6 day event like in the 1800s? Maybe not–but the sport has oodles of potential. Hopefully a few more fast US runners will climb aboard and we can have a string of gold medals like Japan was able to do for 5 plus years in the World Championship. Exciting times.

If 100k's are a decent predictor for 100 miles, you should probably include David Riddle, Andy Henshaw, and probably anyone else who has broken 7:00.

I think I read someone say that Ian Sharman's 12:44 at RR was worth an 11:14 on a track, so maybe he has the best shot at the WR?

Haven't US teams done well at the IAU 100k before 2010, or was it mostly just individual performances?

The substrate question and Matt's comments bring up an interesting point. I agree with giving road performances a priority. I'd rather have someone on the team that has hit that road standard and has proven they can take 6 hours on roads over a fast trail performer. Matt, they aren't carrying over the auto selections from the 2012 race?

I think it is harder to cross from trails to roads with respect to training given athletes of the same ability level. For the most part, you can train for trails. Exceptions are due to things like weak ankles and GI issues during long races. For the roads, any biomechanical issue is going to be exaggerated, and you also need to be able to withstand the general abuse of training and racing on the roads. While the track has many benefits for ultra races, it's not going to be any fun for someone with IT band issues, for example. I think you need to be more genetically blessed biomechanically for roads, and this may also pertain to overall aerobic ability, where I'm not sure if the top 6 trail guys, if you remove proven road performers, have the ability to run between 6:40-6:50 for 100k. That is where the US 100k team has been for the past 3 years.

Some good points Ben. Does anyone know what happened to Andy Henshaw? He absolutely crushed it for about a year there at 100km, but then I haven't seen anything from him in a couple years.

I agree that "equivalent" performances from road 100km and trail 50 mi, that the road 100km should be given preference. What gets tough is when things are equivalent, and when one is clearly better. One reason I like including AR, IAT, and JFK in the selection pool is the relative inaccessibility to 100km road races in this country. There's only a couple opportunities—Mad City, Jeb Smith… anything else? Maybe a track or loop course that allows/verifies a 100km finish. And these races tend to not be as competitive, so they don't draw the top athletes as much.

I was hoping you were involved in Waramaug, I'd have that as the 50k champs, Caumsett is not at an ideal time of the year, to say the least, and it would be nice to have new race for the 50k. I'd heard great things about Waramaug.

No idea who will be at Caumsett. I'm always on the verge of completely retiring from the roads, and this year I'm going to be getting back to snowshoeing with the national champs in VT. That might be same day as Caumsett.

Oh, and yes, that's correct, Ben. No holdover autoqualifiers from the 2012 Champs. Criteria 1 and 3: "(N/A for 2014 due to lack of 2013 World Championship) (qualification valid for the following calendar year World Championship only)"

That adds insult to the injury of not being able run the IAU 100k in 2013 for any auto qualifiers. It's the smart thing to do in terms of the team, but it is still not right. I'm not even sure it is the smart thing to do in terms of the team, as it is hard to predict how people will do overseas until they get there. Prior international experience is probably the best predictor.

Something similar happened when the 2011 IAU 24 Hour was cancelled. At the 2010 event, Scott Jurek had taken silver and set the American record. Yet, he wasn't qualified the next time they held the world championships and couldn't compete.

I do agree that Ian is one to look at when taking a shot at the 100 mile record, you'd be hard pressed to find a better runner for it. You do bring up another interesting discussion about converting trail times to road/track times.

Matt touched on an idea that I also use with the Desert Solstice entry process, which is that the best way to demonstrate competence for a fast ultra is to run a fast ultra. It's not easy to predict how a trail time would have converted to a road time on the same day. I've only had a couple runners apply for Solstice without fast running experience (but plenty of impressive trail times). As anecdotal evidence, they all ran into struggles partway through the race.

It's hard to convert a trail time to a road time, given the huge number of variables at play. I would find a 1:30 handicap for Rocky Raccoon a bit much for his type of performance, I would be curious to see where that figure came from. Then again, I wouldn't put much past Ian. Only one way we'll know, and that's if he can put together a time like that at a race. Here's to seeing it!

That's the point, Nick, the figure was just pulled out of the air to provide an explanation of how Jon Olsen's 11:59 was soft compared to trail performances, and should not be the performance of the year. Considering there have been a few fast performances at RR, but few sub 13hr 100's on the road in the past 3 decades, I agree with you. If Andy Milroy thinks the 100k is a good predictor, I'll stick with that and comparable 50 mile times. Zach ran a 50 mile time similar to guys who ran around 12 hours for 100 miles, so there is some data to support his potential to run a fast 100.

As someone who has done a few road ultras but mostly runs on the trail, I'm not surprised at your observation of fast trail guys at desert solstice. Sometimes I can get away with minimal road miles in preparation for a road ultra, but usually my legs can't take the monotony and pounding unless I've done a decent amount of road training, and that is for shorter events. Has anyone ever run a fast 100 mile time on the track or roads without doing quite a bit of road training? All the fast guys in the 70's and 80's were road studs.

I don't think there's an exact formula you could use for converting a road time to a trail time as it would vary from person to person (I've seen some fast road guys who slow down a lot on even easy trails, for example) as well as the variable conditions in trail races (look at the difference between the cold 2012 WS and boiling 2013 race).

One prediction I'll make is that there are probably runners currently in the US who could beat the 100 mile world record, although it might need a dozen of the contenders to turn up at Desert Solstice to do it. I'd like to give it a go at some point since I think the WR for 100 miles is about the coolest record available in the sport…and the women can definitely lower Ann Trason's mark – just need girls like Lizzy Hawker and Ellie Greenwood (amongst others) to race a track 100.

One obvious problem, familiar to anyone who uses Strava's "Grade Adjusted Pace," is that nobody descends at the limit of their metabolic capacity, since there are so many other factors that limit one's pace on steep downhills, especially over technical terrain. By contrast, while climbing is certainly biomechanically different than running flats, it seems to be a fairly simple matter for a runner to simply do the work output they'd be doing on a flat, but with a slower actual pace (except, perhaps, on very steep and technical terrain). Minetti et al. 2002: "In downhill competitions, athletes do not seem to use the full amount of the available aerobic power for increasing their speed…During downhill running, other criteria such as the maintenance of a reasonable safety factor could be operating to minimize joint and tissue injuries. It is likely that at extreme downhill slopes muscles could not cope with the tendency of the body to accelerate, rather than maintaining a constant speed throughout a controlled constant braking. That would result in the lack of the fine motor control needed to maintain body trajectory on a rough and slippery terrain…This analysis points out how in competitive downhill running, differently from the uphill situation and many other sport activities, 'power without control is nothing.' " http://jap.physiology.org/content/93/3/1039.full

Zach Bitter has proved to be contender and has pushed the limits of speed. He has already broke records, and it seems to be only the beginning of his career. As far as race substrates, if you want to run fast on trail, you need to to train fast on trail, same for road, or mtn running.

As Matt mentioned above, one of the major problems with the road ultra scene right now is the lack of races. The best "known" 100ks are Lake Waramaug (CT) and Mad City (WI), which are a mere two weeks apart. Jeb Smith is only a 50 miler although I think people have extended it before for a 100k qualifier. Therefore, in order to get the highest criterion qualifier (sub-7:20 at a road 100k) you have to make it to one of those two races and hope you have a good day. Personally, I'd love to go for a 100k qualifier this spring but I'm already signed up for Boston which falls right in between Mad City and Lake Waramaug. Anyone know of any road 100ks in February or May?

Hopefully as the sport continues to grow we'll see more opportunities to run fast at 50mi and 100k on the road. For now, though, it is slim pickings.

Also, while we're throwing out names, is Todd Braje still at it? He ran some solid 50 milers and 100ks a couple years ago and could potentially do well at the 100mi track/24hr races. I see from ultrasignup that he ran 7:04 at Mad City and 5:50 at Tussey in 2011.

While I understand the point of having the 100k as the highest criterion, (I can't imagine going on for another 12 miles on the road considering how I feel at 50) that does make it tough with so few 100k's. Boston is overrated, just go to Waramaug! I might even offer to pace if there was interest. The best option for increasing the 100k is extending 50 milers, as you mention, and it seems like that would be easy to do at the Chicago area races.

The 50mile distance is at a bit of a crossroads. While it used to be a more common race distance, with the ever growing popularity of ultra/ trail running and the ever growing participation of "soft" new-comers to the sport, 50Ks have become more and more common. As the generation of runners to come before me have pointed out time and again, what was considered a weak performance 25 years ago at some ultras, is now considered to be a strong showing (that is true even though there is more elite competition today).

One would imagine that more 100Ks will pop up across the county now that WS has decided to market itself as more of an international race. What that means for domestic road 100Ks remains to be seen. I would love to see a US alternative to Comrades, perhaps in Nov, giving people time to qualify to apply to WS.

That's actually a really good thought for the future if people needed a fall qualifier. The Chicago Lakefront 50/50 would be perfect because the 50k distance is already USATF certified (3 loops I think; the 50 mile is 4 loops, all a bit longer). Just need to get the RDs on board in letting you run 100km and you'd be set.